The protein Prothrombin II, also known as Factor II, undergoes a post-synthetic modification in the presence of Vitamin K wherein ten glutamate (GLA) residues in the GLA-domain are carboxylated to g-carboxy glutamic acid. The carboxylation process is aberrant and incomplete in the diseased state and the process by which prothrombin is converted to PIVKA-II (Protein Induced by Vitamin K Absence). PIVKA-II is a large glycoprotein having a 72 KDa molecular mass and known to be elevated in the case of HCC patients (Liebman et al., The New England Journal of Medicine (1984), 310 (22), pages 1427-1431; Fujiyama et al., Hepatogastroenterology (1986), 33, pages 201-205; Marreo et al., Hepatology (2003), 37, pages 1114-1121). At present, available methods for detecting HCC or liver cancer by use of biomarkers are ineffective (Koteish et al., J. Vasc. Interv. Radiol. (2002), 13, pages 185-190; Yuen et al., Best Practice & Research Clinical Gastroenterology (2005), 19, pages 91-99; see also Herai et al., Japanese Journal of Clinical Laboratory Automation (2007), 32(2), pages 205-210; Durazo et al., Journal of Gastroenterology and Hepatology (2008), 23, pages 1541-1548; Yamaguchi et al., Clin. Chem. Lab. Med. (2008), 46(3), pages 411-416). Further, only a few monoclonal antibodies are known which have the binding specificity required to be useful in immunoassays that effectively detect such conditions or to treat such conditions (Naraki et al., Biochemica et Biophysica Acta (2002) 1586, pages 287-298). Thus, a great need exists in oncology for the development of antibodies that can be used effectively for detecting HCC or liver cancer.